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981.
Thai Binh Le Peter C. Hauser Thi Ngoc Mai Pham Thi Lan Phuong Kieu Thi Phuong Quynh Le Quoc Anh Hoang Dinh Chi Le Thi Anh Huong Nguyen Thanh Duc Mai 《Electrophoresis》2020,41(23):1980-1990
In this study, the development of our purpose-made capacitively coupled contactless conductivity detection (C4D) for CE is reported. These systems have been employed as a simple, versatile, and cost-effective analytical tool. CE-C4D devices, whose principle is based on the control of the ion movements under an electrical field, can be constructed even with a modest financial budget and limited infrastructure. A featured application was developed for quality control of antimicrobial drugs using CE-C4D, with most recent work on determination of aminoglycoside and glycopeptide antibiotics being communicated. For aminoglycosides, the development of CE-C4D methods was adapted to two categories. The first one includes drugs (liquid or powder form) for intravenous injection, containing either amikacin, streptomycin, kanamycin A, or kanamycin B. The second one covers drugs for eye drops (liquid or ointment form), containing either neomycin, tobramycin, or polymyxin. The CE-C4D method development was also made for determination of some popular glycopeptide antibiotics in Vietnam, including vancomycin and teicoplanin. The best detection limit achieved using the developed CE-C4D methods was 0.5 mg/L. Good agreement between results from CE-C4D and the confirmation method (HPLC- Photometric Diode Array ) was achieved, with their result deviations less than 8% and 13% for aminoglycoside and glycopeptide antibiotics, respectively. 相似文献
982.
Dr. Svetlozar Ivanov Sebastian Mai Dr. Marcel Himmerlich Dr. Anna Dimitrova Prof. Stefan Krischok Prof. Andreas Bund 《Chemphyschem》2019,20(5):655-664
Electrochemical quartz crystal microbalance (EQCM) with damping monitoring is applied for real-time analysis of solid−electrolyte interphase (SEI) formation in diphenyl octyl phosphate (DPOP) and vinylene carbonate (VC) modified electrolytes. Fast SEI formation is observed for the DPOP containing electrolyte, whereas slow growth is detected in VC-modified and reference electrolytes. QCM measurements in a dry state show considerable reduction of the mass quantity for DPOP and reference samples and minor mass decrease for the SEI layer formed in the presence of VC. The results indicate that VC enhances SEI stability, whereas the addition of DPOP or no additive results in incorporation of loosely attached species, leadubg to SEI instability. Resonance frequency damping, Δw, and dissipation factor, D, are used for analyzing mechanical properties of the SEI layers. The apparent increase of Δw and D during SEI formation in presence of DPOP suggests a pronounced viscoelasticity of the layer. QCM results are compared with surface morphology and chemical composition, revealing excellent agreement of the applied characterization approaches. 相似文献
983.
Nguyen T. My-Thao Huynh T. Thanh-Tam Dang Chi-Hien Mai Dinh-Tri Nguyen T. Thuy-Nhung Nguyen Dinh-Truong Dang Van-Su Nguyen Trinh-Duy Nguyen Thanh-Danh 《Research on Chemical Intermediates》2020,46(3):1975-1990
Research on Chemical Intermediates - The study reports a versatile, cost-efficient and ecofriendly protocol for the synthesis of biogenic silver nanoparticles (AgNPs) using the aqueous extracts of... 相似文献
984.
Nguyen Van Hop Chen Chang Xiong Van Hong Thien Le Nhat Tam Chu Van Hai Truong Huynh Anh Vu Nguyen Quoc Hung Dam Sao Mai 《Chemistry of Natural Compounds》2022,58(3):562-564
Chemistry of Natural Compounds - 相似文献
985.
Mai Gehrke 《Algebra Universalis》2018,79(3):63
This note aims to highlight some of the conceptual contributions to duality theory made by Bjarni Jónsson through the theory of canonical extensions. 相似文献
986.
Dr. Federico Luppi Dr. Nathalie Mai Guillaume Kister Dr. Philip P. Gill Sally E. Gaulter Dr. Christopher Stennett Dr. Eleftheria Dossi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15646-15655
Crystalline polymers such as β-cyclodextrin (βCD) can be modified with polyethylene glycol (PEG) diglycidyl ether cross-linkers (262, 394, 500 Da). In this work, the authors show that the quantity and length of the PEG soft segments influence the solubility and malleability of the products, which are water soluble and easily converted to nitrated analogues under standard reaction conditions. Inert and nitrated derivatives containing longer PEG segments showed the ability to self-heal. The degree of cross-linking and decomposition temperatures and energies depended on the quantity and length of the soft segment. Nitrated cross-linked βCD containing longer PEG segments did not ignite following an electrostatic discharge of 4.5 J. The chemical stability of βCD/PEG binders was tested by heat flow calorimetry at 80 °C. The balanced incorporation of soft PEG and rigid βCD segments was found to improve the processability of cross-linked βCDs and desensitised their nitrated derivatives, offering new solutions for inert and energetic binders. 相似文献
987.
In this research, the slag fibers coming from water‐quenched slags by using thermal plasma technology were successfully prepared and introduced into epoxy resin to be microwave absorber. The fiber‐blowing equipment for manufacturing slag fibers through controlling the nozzle angle and vertical distance from the nozzle to the melt outlet was also studied. The spectroscopic characterization of the formation processes of slag fiber was studied by using X‐ray diffraction (XRD), inductively‐coupled plasma (ICP), differential thermal analysis (DTA) and scanning electron microscopy (SEM). Microwave absorbing properties of the slag fibers and thermal plastic resin were investigated by measuring reflection loss in the 2–18 and 18–40 GHz microwave frequency range using the free space method. It was found that the composite specimens of slag fiber and thermal plastic resin had the best microwave absorption due to the reflection losses between from −4 to −8 dB and from −11 to −17 dB at frequencies between 2–18 and 18–40 GHz. 相似文献
988.
Microencapsulation of Bistetrazol · diammonium (BHT · 2NH3) as a hydrophilic powdery flame retardant was tried by the interfacial reaction method in reverse emulsion. In this microencapsulation method, water droplets containing BHT · 2NH3 and hydrazine as gelation agent for epoxy resin were dispersed in the continuous phase of corn oil. When epoxy resin was added to the continuous phase, BHT · 2NH3 as a core material was microencapsulated by the reaction of epoxy resin with hydrazine on the interface between the surface of water droplet and the continuous phase. The content of the core material from 70 to 85%, and the microencapsulation efficiency from 89 to ca 100% were able to be attained under the experimental conditions adopted here. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
989.
Keggin型缺位杂多阴离子PW11O7-39电催化降解硝基苯 总被引:1,自引:0,他引:1
以Keggin型缺位杂多阴离子PW11O7-39(PW11)为电催化剂,硝基苯(NB)为模型污染物,研究了Na2SO4-NaHSO4介质中PW11O7-39对NB的电催化降解作用.实验结果表明,在pH=2.5,E=-0.6V和O2流速为60mL·min-1的条件下,初始浓度为0.5 mmol·L-1的硝基苯反应80 min即完全降解,反应120 min总有机碳(TOC)去除达42%.硝基苯的电催化降解服从准一级反应动力学模型,室温下其表观速率常数Kobs的大小与NB的初始浓度有关,当NB的初始浓度为0.5,0.9和1.3mmol·L-1时,Kobs值分别为1.0×10-1,6.0×10-2和4.1×10-2min-1. 相似文献
990.
Yuhai Wang Hao Shen Gu Li Kancheng Mai 《Journal of Thermal Analysis and Calorimetry》2010,100(3):999-1008
The crystallization and melting behavior of PP/CaCO3 nanocomposites during thermo-oxidative degradation process were studied using differential scanning calorimetry and X-ray diffraction. The results indicated that addition of nano-CaCO3 and compatibilizer significantly reduced the thermo-oxidative stability of PP. Before degradation, thermal aging resulted in an increase in the melting temperature and crystallinity of PP due to the annealing crystallization. Thermo-oxidative degradation decreased the melting temperature and increased melting range, and caused an increase in crystallinity of PP due to the chemi-crystallization. The investigation also indicated that the influence of degradation on the small crystals were much more significant than that on the large ones. 相似文献